Alaska Extended Forecast Discussion National Weather Service College Park MD 759 PM EDT Tue Oct 28 2025 Valid 12Z Sat 01 Nov 2025 - 12Z Wed 05 Nov 2025 ...Synoptic Overview... The synoptic pattern across the Alaskan domain continues to favor fast-moving cyclones to track west to east through the Aleutians then gradually dissipate over the Gulf of Alaska as a negatively- tilted upper ridge remains stationary across eastern mainland Alaska and further up into the Arctic Ocean in the form of an omega block. ...Guidance Evaluation and Preferences... The ensemble means from the ECMWF, GEFS, and CMC show decent agreement on the above-mentioned synoptic pattern evolution through the medium-range period. Much of the uncertainty is in regard to the timing of the next cyclone potentially entering the western Aleutians early next week. The GFS is near the slow end of the spectrum followed by the UKmet, while the ECMWF and CMC are near the fast end of the spectrum by a few hundred miles to the east on Day 6 Monday. The ensemble means favor toward the faster solution. Toward the end of the medium-range period, both the deterministic and ensemble means show decent agreement on the next significant cyclone to track along the Aleutians with the GFS/GEFS cluster placing the cyclone center very near the island chain while the EC cluster is farther south. The Alaska forecast package was based on a general model consensus of 40% from the 12Z ECMWF/00Z EC mean, 40% from the 12Z GFS/GEFS, and 20% from the 12Z CMC/CMC mean, with the majority of the blend based on the consensus of the ensemble means for Days 7 & 8. This blend yielded an isobaric pattern quite compatible with yesterday's WPC forecasts. ...Weather/Hazards Highlights... The medium-range period will likely begin with a deep cyclone centered over the Gulf of Alaska with its strongest winds likely remaining just off the southern shoreline of mainland Alaska into the Panhandle. Moderate to locally heavy precipitation associated with this cyclone will gradually taper off through the weekend as the cyclone is forecast to steadily weaken. But light to locally moderate precipitation is forecast to linger along the southern shoreline to the Panhandle into midweek. Thereafter, a couple of cyclones appear to track very quickly near/along the Aleutians early to middle of next week, with the subsequent cyclone being the stronger of the two. Unsettled weather appears to be in store for the Aleutians by early next week before reaching the Peninsula possibly by midweek. Pressure pattern appears to favor high winds behind this system. Temperatures will be mostly around average except for the central Brooks Range, and along the eastern Aleutians this weekend when below normal high temperatures are in the forecasts. && Kong Additional 3-7 Day Hazard Information can be found on the WPC medium range hazards outlook chart at: https://www.wpc.ncep.noaa.gov/threats/threats.php WPC medium range Alaskan products including 500mb, surface fronts/pressures progs and sensible weather grids can also be found at: https://www.wpc.ncep.noaa.gov/alaska/ak_5dayfcst500_wbg.gif https://www.wpc.ncep.noaa.gov/alaska/akmedr.shtml https://www.wpc.ncep.noaa.gov/alaska/ak_5km_gridsbody.html